A groundbreaking study has challenged long-held assumptions about the origins of life on Earth. Researchers, led by Dr. Ashley Martin, found that ancient oceans may have been teeming with bioavailable nitrogen 2.75 billion years ago, paving the way for microbial ecosystems to thrive.
The team analyzed stromatolites from Zimbabwe and discovered evidence of hydrothermal ammonium upwelling, suggesting that volcanic activity played a crucial role in early life on Earth. This discovery sheds new light on the biological and chemical conditions that preceded the rise of atmospheric oxygen.
Nitrogen is essential for all known life, but in early Earth’s history, it existed mainly as an inert gas. The transition to complex life required mechanisms to make nitrogen bioavailable in the oceans. The study found unexpected reservoirs of ammonium in deep waters, which were brought to the surface by hydrothermal upwelling.
The findings suggest that nitrogen fixation, a process previously thought to be constrained in pre-oxygen Earth, may have occurred on a larger scale than previously assumed. Volcanic activity 2.75 billion years ago was intense, supplying nutrients to shallow marine environments and potentially driving biological innovations.
This research has major implications for astrobiology, particularly in the search for life on Mars, Europa, and Enceladus. If hydrothermal activity could support life in Earth’s pre-oxygen world, similar ecosystems might exist on other planets or moons with subsurface oceans. The presence of ammonium-rich hydrothermal systems could provide a biosignature for extraterrestrial life.
Source: https://indiandefencereview.com/2-75-billion-year-old-rocks-lifes-origins